This invention relates to a process for the production of 5- or 6-membered heterocyclic compounds corresponding to the general formula (I): ##EQU6## IN WHICH A represents a bivalent chain of 2 or 3 carbon atoms which can also be part of a bivalent, optionally substituted aliphatic, cycloaliphatic, araliphatic or aromatic radical,
B represents a single bond, oxygen, sulphur or the group ##EQU7## and/or arylene radicals, X represents oxygen, sulfur or the group ##EQU8## R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are the same or different and represent hydrogen, halogen, the nitro group, an optionally substituted aliphatic, cycloaliphatic, araliphatic or aromatic radical, R.sup.5, R.sup.6 and R.sup.7 are the same or different and represent hydrogen or an optionally substituted aliphatic, cycloaliphatic, araliphatic or aromatic radical, and n and m are the same or different and represent an integer from 1 to 14 PA1 with lactams corresponding to the general formula (III): ##EQU10## in which B, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, n and m are as defined above, at a temperature of from about 100.degree. to about 300.degree.C in the presence of at least a catalytic quantity of acid and/or acid catalysts. PA1 X, r.sup.5, n and m are as defined above, and PA1 R.sup.8 and R.sup.9 are the same or different and represent hydrogen or an optionally substituted aliphatic, cycloaliphatic, araliphatic or aromatic radical, PA1 R.sup.5, r.sup.7, r.sup.8, r.sup.9, n and m are as defined above.
The sum of n and m not exceeding 15.
A number of compounds of this kind are already known, being in particular derivatives of the above general formula in which X is sulphur or a substituted amino group and in which the carbon chain defined by n is generally short, i.e. generally containing only 1 or 2 carbon atoms.
In general, compounds of this kind are prepared by condensing o-diamines or o-aminothiols either with .omega.-amino acids, in which the amino group is protected or unprotected while the carboxyl group is present either as such or in the form of its nitrile or acid chloride, or with halogen or unsaturated carboxylic acids, in which case the amino group is introduced by aminolysis of the halogen alkyl group, optionally by the Gabriel synthesis, or by the addition of ammonia or amine with existing double bonds.
Thus, 2-(.omega.-aminoalkyl)-benzimidazoles can be obtained for example in accordance with German Pat. No. 1,131,688 and British patent No. 1,023,792, 2-(aminoethyl)-thiazolines in accordance with Japanese Pat. No. 22,389 (1966) and Chem. Pharm. Bull. (Tokyo) 13, 180-8 (1965), and 2-(aminomethyl)- and 2-(aminoethyl)-benzthiazole in accordance with Z.obsc. Chim. 32, 3703-7 (1962) and 34, 1926-30 (1964).
In addition, compounds of formula I can be obtained in accordance with German Offenlegungsschrift No. 2,110,227 by reacting 1,2- or 1,3-diamines, aminohydroxy- or aminothiol-compounds with reactive lactam derivatives, such as lactim ethers or lactim chlorides.
.omega.-aminocarboxylic acids are frequently obtained on an industrial scale by hydrolysing readily available lactams, however the conversion of lactams into the more reactive lactim derivatives involves a considerable outlay. The problem of directly producing heterocycles of the general formula (I) from the corresponding lactam as the starting material, without having to resort to the formation of an intermediate product, has hitherto remained unsolved.